CVE-2026-87665A stack-based buffer overflow vulnerability exists in the Internet Key Exchange (IKEv2) protocol handler on Brocade Fabric OS versions before 10.0.1. The vulnerability occurs when processing initial IKE key exchange requests on extension switches or blades running IPsec-enabled Fibre Channel over IP (FCIP) circuits. An unauthenticated remote attacker can exploit this vulnerability by sending a single, specifically crafted UDP packet (Port 500) containing an oversized Nonce payload. Successful exploitation results in a denial of service (data-plane process crash)